Fact or Crap

well said, sir!

 

One thing to keep in mind is, unlike track cars, your truck has to continue to pump oil on uneven ground. That means it needs an "oversupply" of oil in the pan to compensate. I keep mine full of the factory recommended weight synthetic oil.

If you're that worried about gas mileage look into a Prius.

 

Many engineers have said there is less windage loss when the oil is at a lower level. So there is very likely a benefit to be had from running the oil level near the low mark. But the windage loss statement is a very broad statement and you need to take into consideration individual engines with different pan designs, windage trays, oil capacities, crank throws, how the vehicle is used in real life, etc etc.

Also, just because the oil level is below the full mark does not mean it is underfilled. Anything between the low and full marks is fine. <-- I have made this statement countless times on these TW forums. Every auto manual I have ever read says this area on the dipstick between low and full is the "SAFE ZONE." I don't care if it's just barely above the low mark, the level is OK for normal use/light duty. Been doing this for many years on many vehicles with no issues. Just remember that less oil means less capacity for suspending contaminants and less oil for cooling/smaller heat sink. So the oil *might need to be changed out sooner than a totally full crankcase.

However, on an engine that burns oil, leaks oil, or gets worked hard, I would definitely maintain the oil level at (or very near) the full mark. Or I would just fix the leak

 

So you go to start your engine with 5 quarts in the pan or 3 quarts in the pan, or even a larger pan that stock that holds 10 quarts. How does the oil pump and the engine know the amount of oil in the pan? As long as the oil pump pickup is covered with oil at all times, the engine will be provided the proper amount of oil, and the engine will not be starved. There is no cylinder scoring because the oil pump is flowing the same amount of oil as it would be with 5 quarts, there is no spun rod bearing because the oil pump is flowing the same amount of oil as it would be with 5 quarts. As long as you have enough oil to cover the pickup you are fine. Its called factory of safety. Engines often leak or burn oil and they dont design the oil pan capacity based only on the dots on the dipstick. They are designed to operate on a capacity less than the dipstick tube shows, because not everyone cares about their vehicles as much as enthusiasts do.

You missed the point about the octane as well. They recommend 87 but the engines will run on 85 or 93 because people are careless and dont always watch what gas they put in their vehicle. The engineers compensate it by cutting timing like you said, they do not shut off and leave you stranded on the side of the road. If they were designed to run solely on 87, they would knock and blow up when a careless person puts lower quality fuel in them. Once again, they design them with a factor of safety to run on lower than required fuel.

Cut the ounces and the lbs will come means that you start cutting weight on a race car by saving an ounce here, and an ounce there etc. Saving enough ounces here and there add up to larger weight losses measured in lbs. To put it simply, small changes add up. Reducing windage makes a small change in efficiency. Combined with many other small changes they eventually add up to something measurable.

The initial post talked about running and engine with a little less oil on the dipstick tube, not 1 quart of oil only.

 

You clearly don’t know the first thing about why an engine needs oil or even why it needs to be changed out.

I bet you’re out here thinking that engine oil has one, single purpose: to lubricate (aka - reduce friction in) moving parts. I bet you think oil only reduces friction in the cylinder walls, crankshaft, and crankshaft, and maybe a few other parts.

And I bet the best answer you can muster up is “because detergents” if someone asked you why oil has to be changed every 5k miles.

I bet you think the W in oil ratings stands for ‘weight’.

You’re clueless.
You’re the guy out here that thinks payload ratings on a compact pickup are just a marketing scheme, and loading your Tacoma up with 2500lbs in the bed —“it’ll be fine”

Yes, oil does lubricate moving parts. But it also does a lot of other things. It cools hot components, cleans the engine, absorbs blow-by, absorbs water, prevents corrosion, keeps seals fresh, and removes metal dust from the rotating assembly.
You notice how almost all of those things depend heavily on how new the oil is?

lubrication is whatever. That’s the least demanding property. Keeping parts cool is huge. The oil is a thermal reservoir. As the oil passes through the engine, it absorbs the heat, then it has to be cooled off. What do you think happens when your reservoir of oil is too low? And the oil doesn’t have a chance to cool enough before it’s sent back to the cylinder head to absorb more heat?
You are aware that oil can ‘burn,’ right?
Oil can heat up until it turns to sludge. You know, that nasty black shit on the under side of a valve cover.

The detergents in the oil help keep the inside of the motor clean, and try to dissolve that sludge you just ‘installed’ in your engine by purposely running it low and hot.

Everything oil absorbs: water, blow-by, metal shavings.
(Yes, your oil carries out metal shavings, no they don’t sink to the bottom of the oil pan like in a non-detergent oil setup in a pressure washer or ancient Harley motor.)
Do you think it would be a good idea to have the same amount of metal shavings sprinkled in 1qt of your cars oil, or would you prefer it spread out over 5qts?
The filter removes metal, but what about blow-by and water?
You did know oil absorbs droplets of condensation, no? Or did you think the water just settles to the bottom so it can rust everything, and when you cold-start your motor, it’s just sucking and pumping straight water for a few seconds?
Did you know that the main reason we change oil in our motors is due to excessive blow-by content. Blow-by is primarily unburnt fuel, or gasoline in gas engines. Gasoline dissolves oil (gasoline will wash oil off your cylinder walls), and exhaust gases will make oil acidic.

These 2 things are primarily why oil needs to be changed regularly, and which is why oil change intervals have gotten longer as engine technology has progressed - modern engines have less blow-by and less unburnt fuel than older engines.

These are some very basic facts about oil and lubricartion that would be studied by 3rd year engineering students at any ABET accredited engineering university.

If I catch you telling people on this forum that you’re an engineer again, I will report you for fraud because I suspect you to be a snake oil salesman.

 

Figured I'd throw this out there: I fill up my truck with 5 quarts instead of 5.5 because I'm too lazy to buy the extra quart bottle with my 5 quart jug and I still get the same shitty mileage lol I believe whoever said that is bullshittin

 

Shouldn’t this mass of stupidity be in the third gen section

 

5% change would be less than 1 mpg on most trucks (5% of 20 is 1), which could also be attributed to different gas stations, different temperatures, more/less lead foot driving, or even rounding error. My mileage can vary by 2 mpg or more between tanks.

Doesn't sound very scientific, and definitely not worth running less oil for such a small potential gain.

 

I know right? its like people buy these trucks then try to get the same gas mileage as a corolla. same shit on the evo forums people are like hey how can I make my mpgs just a HAIR better. like fuck off you bought the wrong vehicle if your complaining about mpgs.

 

hmmm so your saying I can run my car on 87 even though it was tuned for 94 and ill be COMPELETELY FINE because the ecu is designed to compensate? makes sense

 

Is your car tuned for 94 with an aftermarket chip/tune? Aftermarket tunes/chips get a few more horsepower by removing the conservatism/reducing saftey factory out of the timing curves and specifically stating they are to be run on XX or higher octane fuel or engine damage can occur. So if you consistently run 87 in your chipped/tuned vehicle you'll have issues.

As for the stock 4.0 Tacoma was optimized to run on 91 as per the owners manual but there are plenty of people on here that run 87. The computer dials back the timing like you said in your previous post.You dont see posts on here about blown up stock engines running 87 do you? Stock vehicles are built with a lot of conservatism for safety and reliability because warranty work is costly not just for monetary reasons but also customer relations reasons.

Another thing, the initial post wasnt about complaining about how bad the Tacomas fuel economy is. No one is complaining about how bad the fuel economy is. The initial post is about some guy on fuely claiming that in his vehicle if you run oil on the low end of the dipstick will you gain 5% increase in mpg. Is this guy running a corolla or a tacoma? It doesnt say. The concept is simple though splitting hairs, running the oil level on the low end of the dipstick vs the top end of the dipstick, you will have less windage. Will there be a difference if accurately and scientifically measured in a controlled environment, yes. Will the difference be significant enough to matter to anyone who uses their truck in the real world? Probably not, just like Schlappesepple says.



.

 

Can't have it all in one place.

 

You may lose hp , but yeah, modern cars can run on lower octane fuel.

 

This thread made me laugh, ... a lot.

The subject doesn't amount to a hill of shit or savings in the grand scheme of things.

I voted crap.

 

Well...this is getting interesting now isn't it?

 

safely? I don't think so. maybe your average grocery getter yes but I highly doubt people are putting 87 in their sports cars

 

Perhaps the fact is that this is crap!

 

It happens all the time bud. Know from personal experience. And what do you mean by safely, wil the engine blow up because of a lower octane fuel? Welcome to the 21st century, automobiles now have knock sensors.

 

Back many years ago when I was around both oval track cars and mountain crawlers we would under fill the cars that went fast from point a to point b because the engine ran in a short burst then was shut down but the crawlers we over filled. Nothing like crawling along near the point of flipping and you are wondering if the sump is still in the oil....I hate changing engines 20 miles up a goat path which is at least 2 hours from the nearest road....

 

Hahaha..... this thread makes me chuckle.